The present invention relates to a light radiator in which, in case that light rays such as solar rays focused by use of a lens system or the like are transmitted to a distant place through an optical conductor cable, and the same are emitted from the optical conductor cable at the distant place and utilized as light energy. The light energy can be radiated in a desired radial direction of the optical conductor rod transmitting the light energy therethrough.
In the recent years, the interest concerning solar rays energy is increasing day by day. Research-and-development thereof is actively performed in various technical fields for effectively utilizing solar energy.
In the case of utilizing the solar ray energy, if solar rays energy is utilized without converting the solar ray energy to electric energy, thermal energy, or the like, it is apparent that there is no conversion loss, and therefore the energy can be utilized most effectively. For instance, the solar rays collected outdoors are guided through an optical conductor cable to a place such as an indoor space needed to be illuminated, or same are guided into the sea for nurturing marine animals and plants. Furthermore, various other methods of utilizing the solar ray energy as a light source have been already proposed. Namely, solar rays are utilized for the propagation of microscopic organism such as chlorella or the like, for promoting the health of the human body, for treating arthritis, neuralgia, bedsores, rheumatism, injuries, bone fractures, or the like and stopping the pain of these diseases, or for the other like purposes.
However, in the case of emitting light rays from the end surface of an optical conductor, the radiation angle of the focused light rays turns out to be approximately 45.degree.. Such light rays are considered to become nearly equal to a spot light source, so that the area and the direction of light rays radiation are limited. Consequently, it is not always possible to obtain a satisfactory light source.
In order to overcome such defect, the present applicant has previously proposed in various ways light radiators in which light rays transmitted through the optical conductor cable, as mentioned above, are guided into the optical conductor rod and radiated in a radial direction of the optical conductor rod.
However, in such proposed light radiators, the light rays are mainly radiated approximately uniformly in the radial direction of the optical conductor rod ranging over the entire angle of radiation. Consequently, it is impossible to radiate the light rays in a specially designated radial direction of the optical conductor rod, and therefore the light rays cannot be utilized effectively. The above-mentioned arrangement was a disadvantage of the aforementioned proposed light radiators.